Description
A flaw in Node.js 20's HTTP parser allows improper termination of HTTP/1 headers using `\r\n\rX` instead of the required `\r\n\r\n`.
This inconsistency enables request smuggling, allowing attackers to bypass proxy-based access controls and submit unauthorized requests.
The issue was resolved by upgrading `llhttp` to version 9, which enforces correct header termination.
Impact:
* This vulnerability affects only Node.js 20.x users prior to the `llhttp` v9 upgrade.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| nodejs | node | 4.0 – < 4.*, 5.0 – < 5.*, 6.0 – < 6.*, 7.0 – < 7.*, 8.0 – < 8.*, 9.0 – < 9.*, 10.0 – < 10.*, 11.0 – < 11.*, 12.0 – < 12.*, 13.0 – < 13.*, 14.0 – < 14.*, 15.0 – < 15.*, 16.0 – < 16.*, 17.0 – < 17.*, 18.0 – < 18.*, 19.0 – < 19.*, 20.0 – ≤ 20.19.1 | 4.* |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | node-undici | 7.15.0+dfsg+~cs3.2.0-1 | — |
| Debian 13 | node-undici | No fix yet | — |
| Debian 12 | node-undici | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 9 | nodejs +3 | 1:20.19.2-1.module+el9.6.0+23146+be9976bd | RHSA-2025:8468 |
| RHEL 9 | nodejs-nodemon | 3.0.1-1.module+el9.6.0+23146+be9976bd | RHSA-2025:8468 |
| RHEL 9 | nodejs-packaging +1 | 2021.06-4.module+el9.6.0+23146+be9976bd | RHSA-2025:8468 |
| RHEL 9 | npm | 1:10.8.2-1.20.19.2.1.module+el9.6.0+23146+be9976bd | RHSA-2025:8468 |
| RHEL 8 | nodejs +3 | 1:20.19.2-1.module+el8.10.0+23139+21ba74c5 | RHSA-2025:8514 |
| RHEL 8 | nodejs-nodemon | 3.0.1-1.module+el8.10.0+23139+21ba74c5 | RHSA-2025:8514 |
| RHEL 8 | nodejs-packaging +1 | 2021.06-4.module+el8.10.0+23139+21ba74c5 | RHSA-2025:8514 |
| RHEL 8 | npm | 1:10.8.2-1.20.19.2.1.module+el8.10.0+23139+21ba74c5 | RHSA-2025:8514 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 8 | nodejs +3 | 1:20.19.2-1.module_el8.10.0+4007+01f7d99b | ALSA-2025:8514 |
| AlmaLinux 8 | nodejs-nodemon | 3.0.1-1.module_el8.10.0+3982+85c136aa | ALSA-2025:8514 |
| AlmaLinux 8 | nodejs-packaging | 2021.06-4.module_el8.10.0+3987+dbda4426 | ALSA-2025:8514 |
| AlmaLinux 8 | nodejs-packaging-bundler | 2021.06-4.module_el8.10.0+3958+472a6467 | ALSA-2025:8514 |
| AlmaLinux 8 | npm | 1:10.8.2-1.20.19.2.1.module_el8.10.0+4007+01f7d99b | ALSA-2025:8514 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 9 | nodejs | 1:20.19.2-1.module+el9.6.0+32143+ae966e5b | RLSA-2025:8468 |
| Rocky Linux 9 | nodejs-nodemon | 3.0.1-1.module+el9.5.0+31770+0da7192d | RLSA-2025:8468 |
| Rocky Linux 9 | nodejs-packaging | 2021.06-4.module+el9.5.0+31770+0da7192d | RLSA-2025:8468 |
| Rocky Linux 8 | nodejs | 1:20.19.2-1.module+el8.10.0+1988+437f3d23 | RLSA-2025:8514 |
| Rocky Linux 8 | nodejs-nodemon | 3.0.1-1.module+el8.9.0+1760+903d54b9 | RLSA-2025:8514 |
| Rocky Linux 8 | nodejs-packaging | 2021.06-4.module+el8.9.0+1419+1f26ef47 | RLSA-2025:8514 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP6 | nodejs20 | 20.19.2-150600.3.12.1 | SUSE-SU-2025:02045-1 |
| SLES 15 SP5 | nodejs18 | 18.20.8-150400.9.39.1 | SUSE-SU-2026:4261-1 |
| SLES 15 SP5 | nodejs20 | 20.19.2-150500.11.21.1 | SUSE-SU-2025:02039-1 |
| SLES 15 SP4 | nodejs16 | 16.20.2-150400.3.42.1 | SUSE-SU-2026:4355-1 |
| SLES 15 SP4 | nodejs18 | 18.20.8-150400.9.39.1 | SUSE-SU-2026:4261-1 |
| SLES 12 SP5 | nodejs18 | 18.20.8-8.44.1 | SUSE-SU-2026:4248-1 |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 15 SP5 | nodejs18 | 18.20.8-150400.9.39.1 | SUSE-SU-2026:4261-1 |
| SLES for SAP 15 SP5 | nodejs20 | 20.19.2-150500.11.21.1 | SUSE-SU-2025:02039-1 |
| SLES for SAP 15 SP4 | nodejs16 | 16.20.2-150400.3.42.1 | SUSE-SU-2026:4355-1 |
| SLES for SAP 15 SP4 | nodejs18 | 18.20.8-150400.9.39.1 | SUSE-SU-2026:4261-1 |
| SLE HPC 15 SP5 | nodejs18 | 18.20.8-150400.9.39.1 | SUSE-SU-2026:4261-1 |
| SLE HPC 15 SP5 | nodejs20 | 20.19.2-150500.11.21.1 | SUSE-SU-2025:02039-1 |
| SLE HPC 15 SP4 | nodejs16 | 16.20.2-150400.3.42.1 | SUSE-SU-2026:4355-1 |
| SLE HPC 15 SP4 | nodejs18 | 18.20.8-150400.9.39.1 | SUSE-SU-2026:4261-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 15.6 | nodejs20 | 20.19.2-150600.3.12.1 | SUSE-SU-2025:02045-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | nodejs20 +4 | 1:20.19.2-1.amzn2023.0.1 | ALAS2023-2025-1010 |
| Amazon Linux 2023 | nodejs20-npm | 1:10.8.2-1.20.19.2.1.amzn2023.0.1 | ALAS2023-2025-1010 |
| Amazon Linux 2023 | v8-11.3-devel | 3:11.3.244.8-1.20.19.2.1.amzn2023.0.1 | ALAS2023-2025-1010 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | nodejs | No fix yet | — |
| Azure Linux 2 (CBL-Mariner) | nodejs18 | No fix yet | — |
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | nodejs-16 | 16.20.2-r15 | — |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
Third-party code, not reviewed by us. Public PoCs are sometimes fake or contain malware. Read the code first and run it only in an isolated lab, against systems you are authorised to test.
GitHub 1 repository
-
abhisek3122/CVE-2025-23167 ★ 1 · Jul 15, 2025
Working exploit for CVE-2025-23167 – HTTP request smuggling in vulnerable Node.js 20.x versions before 20.19.2
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Advisories 12
- ALSA-2025:8514 Important: nodejs:20 security update AlmaLinux Security Advisories · Nov 6, 2026
- SUSE-SU-2026:4355-1 Security update for nodejs16 SUSE / openSUSE Security Updates · Sep 29, 2026
- WID-SEC-2025-1055 Node.js: Mehrere Schwachstellen BSI CERT-Bund (WID) · Sep 28, 2026
- SUSE-SU-2026:4261-1 Security update for nodejs18 SUSE / openSUSE Security Updates · Sep 18, 2026
- SUSE-SU-2026:4248-1 Security update for nodejs18 SUSE / openSUSE Security Updates · Sep 18, 2026
- RHSA-2025:8514 Red Hat Security Advisory: nodejs:20 security update Red Hat Security Advisories (RHSA) · Aug 7, 2026
- RHSA-2025:8468 Red Hat Security Advisory: nodejs:20 security update Red Hat Security Advisories (RHSA) · Aug 7, 2026
- SUSE-SU-2025:02045-1 Security update for nodejs20 SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:02039-1 Security update for nodejs20 SUSE / openSUSE Security Updates · Mar 23, 2026
- RLSA-2025:8468 Important: nodejs:20 security update Rocky Linux Security Advisories · Oct 7, 2025
- RLSA-2025:8514 Important: nodejs:20 security update Rocky Linux Security Advisories · Jul 29, 2025
- ALAS2023-2025-1010 Important: nodejs20 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Jun 10, 2025